Shelter building caterpillars act as ecosystem engineers by creating and maintaining leaf shelters, which are then colonized by other arthropods. Foliage quality has been shown to influence initial colonization by shelter-building caterpillars. However, the effects of plant quality on the interactions between ecosystem engineers and their communities have yet to be studied at the whole plant level. We examined how leaf tying caterpillars, as ecosystem engineers, impact arthropod communities on
Leaf shelter construction by herbivorous insects can improve leaf quality, sometimes changing resultant herbivory. In two experiments in a Missouri (USA) deciduous forest we quantified the impact of leaf tie construction and changes to leaf quality on subsequent leaf damage. First, using eight Second, we created experimental leaf ties, protected from herbivores, on the same
- NSF-PAR ID:
- 10442976
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Ecological Entomology
- Volume:
- 48
- Issue:
- 1
- ISSN:
- 0307-6946
- Page Range / eLocation ID:
- p. 69-80
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Quercus alba (white oak), and the modifying effect of foliage quality on these interactions. We removed all leaf tying caterpillars and leaf ties on 35Q. alba saplings during the season when leaf tying caterpillars were active (June–September), and compared these leaf tie removal trees to 35 control trees whose leaf ties were left intact. Removal of these ecosystem engineers had no impact on overall arthropod species richness, but reduced species diversity, and overall arthropod abundance and that of most guilds, and changed the structure of the arthropod community as the season progressed. There was an increase in plant-level species richness with increasing number of leaf ties, consistent with Habitat Diversity Hypothesis. In turn, total arthropod density, and that of both leaf tying caterpillars and free-feeding caterpillars were affected by foliar tannin and nitrogen concentrations, and leaf water content. The engineering effect was greatest on low quality plants, consistent with the Stress-Gradient Hypothesis. Our results demonstrate that interactions between ecosystem engineering and plant quality together determine community structure of arthropods onQ. alba in Missouri. -
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We conducted an experiment involving three tree species, namely:
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Piscidia piscipula frequency had a negative linear effect onM. zapota leaf‐chewer damage, whereas conspecific density did not affect chewer damage on this species. In contrast, density and frequency had non‐linear effects onC. dodecandra chewer damage, namely positive (hump‐shaped) and negative (U‐shaped) relationships, respectively. In addition, density and frequency had positive linear effects onC. dondecandra damage by leafhoppers.These findings call for more work jointly assessing plant inter‐specific variation in density‐ and frequency‐dependent variation in herbivory and its underlying drivers.
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Using a phylogenetic approach, we quantified anatomical, compositional and climatic variables from 40 deciduous and 45 evergreen
Quercus species from across the Northern Hemisphere growing in a common garden.Deciduous species from shorter growing seasons tended to have leaves with lower LMA and leaf thickness than those from longer growing seasons, while the opposite pattern was found for evergreens. For both habits, LMA and thickness increased in arid environments. However, this shift was associated with increased leaf density in evergreens but reduced density in deciduous species.
Deciduous and evergreen oaks showed fundamental leaf morphological differences that revealed a diverse adaptive response. While LMA in deciduous species may have diversified in tight coordination with thickness mainly modulated by aridity, diversification of LMA within evergreens appears to be dependent on the infrageneric group, with diversification in leaf thickness modulated by both aridity and cold, while diversification in leaf density is only modulated by aridity.
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Summary Understanding the pronounced seasonal and spatial variation in leaf carboxylation capacity (
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